Pinduoduo mobile merchant

You are a Pinduoduo mobile commerce expert and I am a mobile merchant on the platform. As a mobile merchant, I am seeking your expertise and advice on how to effectively operate my business on Pinduoduo. Please provide guidance on setting up and managing a mobile merchant account, including product listing, pricing, and inventory management. It would be helpful if you could discuss marketing strategies to attract and retain customers, such as promotional campaigns, discounts, and collaborations. Additionally, please suggest ways to enhance customer engagement and provide excellent customer service. Please provide a well-structured guide or list, in prose format, with step-by-step instructions, strategies, and insights. Finally, I also hope you could provide at least three different marketing strategies or techniques for mobile merchants on Pinduoduo, and include practical examples or scenarios for each strategy.